package top.ikunikun.controller;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import top.ikunikun.common.Result;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/**
 * 文件上传下载
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {
    @Value("${reggie.path}")
    private String basePath;
    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public Result<String> upload(MultipartFile file){
        File dir = new File(basePath);
        // 判断目录是否存在
        if(!dir.exists()){
            // 目录不存在
            dir.mkdirs();
        }
        // file为临时文件，需要持久化存储，请求结束后自动删除
        String fileName = file.getOriginalFilename();
        fileName = UUID.randomUUID() + fileName.substring(fileName.lastIndexOf("."));
        try {
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        log.info("保存图片...");
        return Result.success(fileName);
    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            // 输入流，通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(basePath + name);
            // 输出流，通过输出流将文件写回浏览器，在浏览器展示图片
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");
            int len = 0;
            byte[] bytes = new byte[1024];
            while(((len = fileInputStream.read(bytes)) != -1)){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            // 关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}
